Katarina/Annie bug?

Sorry for the video's lag, try to understand the problem. Problem: Annie has the red bar (the one which should stun). She targets a katarina and launches her q. The flame reaches katarina and in the same instant katarina uses shunpo to jump on top of annie, nullifying annie's stun and damage. Meanwhile annie stil has the red bar. By my sources i know annie's flame cannot be dodged. Ex: you recall, annie targets you with her q, after some moments the flame reaches you at base stunning and/or dealing damage. Answer: This may be a bug, or katarina is untargatable during her shunpo, something that isn't mentioned in the ability's description.